1. Field of the Invention
The present invention relates to a semiconductor device and a method of manufacturing the semiconductor device, and particularly to a semiconductor device that uses a transistor for field shield and a method of manufacturing the semiconductor device.
2. Description of Related Art
As for a semiconductor device such as DRAM (Dynamic Random Access Memory), there is a semiconductor device in which a large number of ward lines having the same structure are disposed in parallel and the first out of every three word lines is regarded as a dummy word line to isolate active fields (see Japanese Patent Application Laid-Open No. 2008-192681). The other word lines (word lines that are not dummy word lines) make up gate electrodes of cell transistors. According to the configuration, when seen in the direction of a bit line, there are two cell transistors included in one active field.